Currently, electronic device process techniques are focused on manufacturing flexible or stretchable electronic devices so as to achieve wearable computers. In particular, process techniques for stretchable electronic devices are being ambitiously developed based on the prediction that silicon-based hard electronic devices will be changed in the future into flexible electronic devices that may be utilized in daily lives.
Accordingly, thorough research into advancements in process techniques for stretchable electronic devices is ongoing. Especially, stretchable electronic devices having elements and connection lines in two-dimensional form have been developed, and the structure thereof where strain is intensively applied to the connection lines is in the spotlight. A manufacturing method of a stretchable electronic device includes forming driving elements and electronic elements having connection lines able to absorb strain on an existing hard substrate, and then transferring the electronic elements to a stretchable polymer-based film. The connection lines of the stretchable electronic device thus manufactured have a zigzag structure or a pop-up structure so as to be adapted for two-dimensional stretching, and may thus absorb most strain applied thereto.
However, technical limitations are recently imposed on such process techniques. Existing studies have proposed techniques in which elements and connection lines are two dimensionally integrated on a plane so as to be stretchable. As such, the connection lines covered with only a very thin protective layer may undergo intense strain. Hence, such a two-dimensional stretchable electronic device is very weak to external force, and thereby shorting of the connection lines may easily occur and integration is possible only on a plane, making it difficult to achieve integration in a vertical structure and thus exhibiting a low degree of integration.